Brit actor accent question

 Alun Armstrong.

He plays in the BBC TV series New Tricks. I like his accent so much I catch myself using it on certain words. "What" is it? I looked him up on IMDB and learned he's from Annfield Plain, County Durham. So for a few minutes I assumed this was a County Durham accent.

Then I watched Shakespeare Retold and heard what sounded like the same accent coming out of the mouth of Bill Paterson (playing Theo in A Midsummer Night's Dream), who is from Glasgow, Scotland.

It occurred to me that Armstrong may have been born in Annfield Plain but spent his childhood in Scotland, or that Paterson, born in Scotland, grew up in County Durham, or that either or both are "acting" the accent and sound completely different in their non-working lives.

Whatever the case, I'd like to know where that broad-'A' sound originates. In my next life I think I'd like to live there.